<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>

<body>
    <button>发送请求</button>
    <button>取消发送</button>
    <script>
        const btns = document.getElementsByTagName('button');
        console.log(btns);
        let xhr = 0;
        btns[0].addEventListener('click', function () {
            xhr = new XMLHttpRequest();
            xhr.open('GET', 'http://127.0.0.1:8000/delay');
            xhr.send();

        });
        // abort
        btns[1].addEventListener('click', function () {
            xhr.abort();
        });
    </script>
</body>

</html>